ABC News(NEW YORK) — As President-elect Donald Trump prepares a team that will transition into the White House this January, world leaders are preparing for their own transition: a relationship with the next U.S. president.

In an interview on Portuguese television, Syrian President Bashar al-Assad, who has kept a firm grip on power in Syria despite five years of civil war, said a Trump administration would be a “natural ally” to Syria if Trump goes after terrorists.

When told Trump seemed ready to work with Syria to fight ISIS, Assad responded positively, but also cautioned that Trump must “deliver.”

“Of course, I would say this is promising, but can he deliver? Can he go in that regard? What about the countervailing forces within the administration, the mainstream media that were against him? How can he deal with it?” Assad asked. “That’s why for us it’s still dubious whether he can do or live up to his promises or not. That’s why we are very cautious in judging him, especially as he wasn’t in a political position before.”

“So, we cannot tell anything about what he’s going to do, but if, let’s say if he is going to fight the terrorists, of course we are going to be ally, natural ally in that regard with the Russian, with the Iranian, with many other countries who wanted to defeat the terrorists,” he added.

Russian President Vladimir Putin congratulated Trump by telegram, expressing hope that the two could repair U.S.-Russian relations that have deteriorated over Russia’s role in Syria and its ongoing military intervention in Ukraine.

In a phone call between Putin and Trump on Tuesday, the men spoke about “the extremely unsatisfying state of Russian-American relations, but also expressed themselves in favor of active joint work for their normalization and opening the path to constructive cooperation on the widest range of questions,” according to the Kremlin.

“In particular, the importance was underlined of the creation of a reliable basis for bilateral connections on the way to develop their economic trade components,” the Kremlin said.

Trump told Putin he is “very much looking forward to having a strong and enduring relationship with Russia and the people of Russia,” according to his transition team.

Philippine President Rodrigo Duterte has congratulated Trump on his “well-deserved victory” and signaled that he and Trump would work well together.

One country that hasn’t issued the president-elect congratulations: North Korea. North Korean leader Kim Jong-un has not yet commented on the U.S. presidential election, but Trump has said he would be open to talking to the North Korean dictator. Trump even said last June he would host Kim in the United States.